Pump and injector nozzle for diesel engines



Jan. 5, 1937. A. sHUMAKE PUMP AND INJECTOR NOZZLE FOR DIESEL ENGINES lFiled. July 2, 1934 Patented Jan. 5, 1937 PATENT oFFlcE PUMP AND INJECTOR NOZZLE FOR DIESEL ENGINES Alton Shumake, Huntington Park, Calif.

Application July '2, 1934, kSerial No. v733,435

2 Claims.

My invention relates to a pump and injector nozzle that isespecially designed for use in connection with Diesel engines and the principal objects of my invention are, to generally improve upon and simplify 'the construction of the existing forms of Diesel engines, pumps and injector nozzles and to provide a relatively simple, practical and inexpensive pump and nozzle that will A produce constant injection pressure during starting, idling or top speeds of'engine operation and insuring an atomized fuel for perfectcombustion and for smooth operation without excess pressure on the pump or the fuel lines leading thereto and therefrom.

A further object of my invention is, to provide a pump that will inject fuel only at the proper time, even though vthe engine throttle be rapidly reciprocated by hand, which is sometimes done in starting an internal combustion engine and further, to provide means whereby the pump will not inject the fuel if the engine rolls backward on compression. i

With the foregoing and other objects in view my invention consists in certain novel features of construction and arrangementsof parts that will be hereinafter more fully described and claimed and `illustrated in the accompanying drawing in which:

Fig. 1 is a section taken on a medial line lengthwise through my improved pump and injector nozzle.

Fig. 2 is a vertical section 2--2 of Fig. 1.

Fig. 3 is va detail section taken on the lineV 3-3 of Fig. 2.` l

Fig. 4 is a fragmentary detail section showing a modiiied form of the bell crank that is utilized for imparting reciprocatory movement to the pumppiston. l

Referring by numerals to the accompanying drawing which'illustrates a preferred embodiment of myrinvention, 'Ill designates the pump housing having one -or more removable walls, such as I l, and formed at the top of said houstaken on the line l" ingis a block I2.

Located in the lower portion of housing I0, and journaled in the side walls thereof, is a shaft I3, one end of which projects 4beyond one of the walls of the housing, and rigidly fixed on said projecting end is a ring I4, i

Formed in the periphery of this ring is a notch- "F5, provided withshoulders at both ends. y

`Loosely mountedon the projecting end of shaft I3 and `enclosing ring Hi, is a housing I6, that posit-iv-elydriven from the engine with which the pump is associated, in any suitable manner. In the present instance I have shown the driving means including a sprocket wheel Il that is directly connected to housing I6.

Formed in housing I6, and communicating with the chamber occupied by ring I4, is a chamber I8, and adapted to occupy either end of said chamber is a spring pressed pawl I9, the point of which is adapted to engage one of the shoulders at the ends of notch I5 in ring Ill.

The construction` just described is employed in order that the shaft I3 maybe driven in the proper directionfrom either `side of the pump and to conform withv the` direction of travel of the driving means.

Rigidly secured to shaft I3, within'the hous` ing, is a cam 20 having an abrupt drop or shoulder 2l, and in order to resist wear the Vgreater portion of the curvedvface of this cam is provided with a layer 22 of hard tough wear resisting metal. i A

Seated in the underside of the head I2 is a tubular fitting 23, the interior of which provides a chamber 2B which functions as a piston chamber andarranged in the lower end of fitting 23 is a gland or stuffing box 25. Y

Mounted for reciprocatory movement through gland 25 and the piston chamber 24, is a piston 26, the lower end of which carries a disc 2l.

Screw seated inthe bottom of the housing I0 and in direct alignment with the fitting 23, is a lplug 28 provided in its upper portion with an axial chamber 29.

Mounted for reciprocatorymovement in chamber 29 is a plunger 30 carrying at its upper end a disc 3| that bears directly against the underside of disc 21.

Interposed between disc 3l and a shoulder 32 that is formed on the intermediate portion of plug 28 is an expansivecoil spring 33.

Journaled in theside walls of housing I0 above shaft "I3 are the ends of a shaft 34 and loosely mounted thereon is a rocker arm 35 in the form of a bell crank.

Removably mounted on the lower end of the vertical arm of this bell crank, is a wear resisting member 36, preferably formed of hard tough metal, and which lmember engages the irregular surface of cam 20.

In some instances it may be found desirable to utilize at the lower end of the vertical arm of the bell crank, a small anti-friction member, for instance, aroller such as 31, Fig. 4.

The outer portion of the lhorizontal member of the rocker arm 35 is bifurcated as designated by 38 and this portion of said arm rests directly on top of disc 21 that is carried by the pump plunger 26.

J ournaled in the side walls of housing III above the horizontal member of rocker arm 35 are the ends of a shaft 39, and carried by said shaft and positioned directly above the horizontal member of the rocker arm, is an eccentric 40. This eccentric, which is shifted to different positions as shaft 39 is rotated, functions to limit the upward swinging movement of the horizontal member of the rocker arm and, consequently, controls the volume of fuel that is delivered by the pump plston on its injection stroke.

One end of shaft 39 extends beyond one side of the pump housing and carries a short crank arm 4I, to which is connected one end of an operating lever 42, which latter is capable of manual manipulation so as to partially rotate shaft 39 and correspondingly change the position of the volume control eccentric 40.

Formed in block I2, adjacent to fitting 23, is a vertically disposed chamber 43 and screw-seated in the lower portion of said chamber is a depending bearing 44, on the lower end of which is located a gland or stufling box 45. A rod 46 extends axially through this bearing 44 and its gland, and adjustably carried by the lower end of said rod is a disc 41.

The bifurcated end of the horizontal member of rocker arm 35 bears on top of disc 41 at a point beyond the point where said bifurcated end bears on disc 21.

Formed in block I2, immediately above the chamber 43, is a chamber 48 and a port 49 connects the upper end of chamber 43 with the lower end of chamber 48.

Normally closing port 49 is a downwardly seating ball check valve 58 that is forced downward by a relative light coil spring 5I, which latter extends upward through chamber 48 and bears against a plug 52 that is removably seated in the upper end of chamber 48.

Check Valve 50 is adapted to be unseated as rod 46 moves to its upper limit of movement and which upward movement is effected by an expansive coil spring 53 that is arranged on the upper portion of rod 46 and which bears against the underside of a fiange or collar 54 that is carried by said rod.

The inner end of a nipple or coupling 55 communicates with the upper portion of chamber 43 and said nipple or fitting is connected in any desired manner to a source of liquid hydrocarbon supply.

Formed through block I2 in direct alignment with the piston chamber 24, is a short vertically disposed duct 56 and connecting the intermediate portion of this duct and the intermediate portion of chamber 48, is a duct 51.

Seated in the top of block I2 and communicating with duct 51, is a nipple or fitting 58, within which is formed a valve seat, and normally resting thereupon is an upwardly opening ball check valve 59 that is forced downward under the influence of a light expansion spring 60.

The injection nozzle forming a part of my invention, comprises a plug 6I, having a portion that is screw-seated in the wall or head of the engine cylinder and removably seated in said plug and extending axially therethrough, is a tubular member 62, provided at its distal end with a tapered nozzle 63 capable of converting liquid hydrocarbon into fine spray as it discharges from said nozzle.

Removably seated ln the rear or lower end of the tubular member 62, is a nipple or fitting 64, the end of which within said tubular member provides a seat for a spring pressed ball check valve 65.

Located directly in front of the jet nozzle 63, is a heating element 66, preferably a coil of wire, and leading from both ends of said coil, through plug 6I, to small plugs 61 that are located on the opposite sides of plug 6 I are suitable electric conductors 68 that are suitably insulated from said plug 6I.

One of the small plugs 61 is insulated from plug 6I and seated in said insulated plug, is a screw 69 that contacts with the corresponding conductor 68 and to which screw is connected a conductor 10 that leads from a battery or other source of electric current supply.

The opposite conductor 68 is secured to the opposite plug 61 by a screw 1I, and carried by the latter, is a washer 12 that contacts with the body of plug 6I, thereby grounding the current that is delivered to and passes through the heating element 66.

Leading from fitting 58 to fitting 64, is a suitable duct or conduit 13.

The operation of my improved pump and injector nozzle is as follows:

As housing I6 is roated, pawl I9 engages one end of the notch I5 in ring 64, thereby imparting rotary motion to shaft I3, and the cam 29 carried by said shaft engages the lower portion of the vertical member of rocker arm 35 and swings the same outward. Such movement swings the horizontal member of the rocker arm downward, and the engagement of the bifurcated portion 38 of said horizontal member with disc 21 forces plunger 30 downward in plug 28 against the resistance oiiered by spring 33.

Thus piston 23 is drawn downward to its limit of movement and on such downward, or suction, stroke, liquid hydrocarbon will be drawn by suction from the source of supply through fitting 55, chamber 43, port 49, past upwardly opening check valve 50 into chamber 48, thence through duct 51 and duct 56 into the piston chamber 24.

As the lower end of the depending member of rocker arm 35 rides off the abrupt shoulder 2I on the cam, the rocker arm will be quickly swung on its axis under the influence of spring 33 so that the horizontal member of said rocker arm will move upward until it is stopped by the adjustable eccentric 40.

As piston 26 is moved upward or inward on the injection stroke, the liquid hydrocarbon trapped in the piston chamber and duct 56 will be forced through fitting 68 past check valve 59 and thence through connection 13 to and through fitting 64, past check valve and through tubular member 62.

'Ihe liquid hydrocarbon in discharging from nozzle 63 will be in a nely divided spray form and in such condition it will strike against the heating element 66 to be vaporized and ignited.

It will be understood that heating element 66 is highly heated as a result of the electric current passing therethrough.

During the downward or suction stroke of piston 26, rod 46, which is forced upward with respect to the bifurcated end of the rocker arm `35 by spring 53, holds ball check valve 50 off its seat so as to insure free fiow of liquid hydrocarbon from the source of supply into the piston chamber 24 and just before rod 46 reaches the end of its downward travel as a result of pressure applied by the bifurcated end of the rocker arm, the upper end of said rod 46 leaves ball check valve 50 so that the same is permitted to seat under the influence of spring 5l just before the depending member of rocker arm rides off 'the liquid lubricant so as to provide an oil bath for the cam 20, rocker arm and other operating parts within said housing. i

The clearance between the upper end of rod 46 and the ball check valve 50 may be accurately regulated by adjustment of the disc 41 on the lower end of said rod 46.

When arm 36 drops oi shoulder 2l, spring 53 is not strong enough to overcome the inertia of the bell crank 35 and the latter is swung upon its fulcrum 34 by the expansive power of the relatively heavy spring 33. As piston 26 moves upward in chamber 24, pressure is built up in said chamber and the chambers 56 and 51 and this pressure being relatively heavy, for instance, from 1,000 to 6,000 pounds maintains ball check 5U upon its seat.

Spring 53 functions only to overcome the friction between rod 46 and sleeve 44 and to overcome the tension of the lighter spring 5I.

Thus in operation, valve 50, in addition to serving as an ordinary check valve, functions to prevent the engine from receiving an injection when not needed or at the wrong period. In other words, the injection of fuel takes place only at the proper time in the cycle of operations. Valve 50 is held open by rod 46 during an indenite period before arm 36 contacts with the surface of cam 20, and this period is variable under different speeds of the engine.

The parts of the injector nozzle must be arranged and adjusted so that pressure is built up in chambers 24, 56, 51, and 48, before the upper end of rod 46 contacts with ball check 50, which latter is under heavy pressure. When this heavy pressure is relieved due to the fuel charge being forced into the engine cylinder, rod 46 unseats valve 50, thereby permitting variation of the eccentric 40 without injecting fuel into the engine cylinder.

The adjustable eccentric 40 provides simple and eifective means for controlling the stroke of the rocker arm and consequently controlling the volume of liquid hydrocarbon that is delivered to and through the injector nozzle by the pump.

The provision of the pawl between the housing I6 and ringv I4 prevents injury or breakage of any of the parts of the pump in the event that the engine should for any reason turn backward while in operation.

The liquid hydrocarbon delivered to the pump may be under pressure or it may ow by gravity.

Thus it will be seen that I have provided a pump and injector nozzle for Diesel engines that is relatively simple in construction, inexpensive of manufacture and very effective in performing the functions for which it is intended.

My improved pump insures constant injection pressure during starting, idling and top speed of engine operation and the injection nozzle insures an atomized fuel for proper combustion and smooth operation without excess pressure on the pump. or the connections between the pump and nozzle.

The pump operates so as to inject fuel only at the proper time and the fuel will not be injected if the engine rolls backward during compression stroke.

It will be understood that minor changes in the size, form and construction of the various parts of my improved pump and injector nozzle for Diesel engines may be made and substituted for those herein shown and described without departing from the spirit of the invention, the scope of which is set forth in the appended claims.

I claim as my invention:

l. In a liquid hydrocarbon fuel pump, a housing provided with a piston chamber, a fuel inlet duct leading to said chamber, a spring pressed check valve located in said duct for preventing rearward flow of liquid fuel through said duct, a spring pressed rod for normally holding said check valve off its seat, a piston arranged for reciprocatory movement in the piston chamber, a spring for yieldingly resisting the suction stroke of the piston, a fulcrumed rocker arm for moving the piston against the resistance of the last-mentioned spring, a cam for actuating said rocker arm, adjustable means carried by said spring pressed valvey unseating rod and adapted to be engaged by the rocker arm for moving said spring pressed rod lengthwise only in the direction permitting the check valve to rest on its seat, said check valve seating as said rocker arm approaches the limit of its movement in imparting suction movement to the piston, the spring associated with said rod being stronger than the spring associated with said check valve, and weaker than the spring associated with said piston.

2. In a liquid hydrocarbon fuel pump, as set forth in claim 1, a rotary adjustable member for controlling the swinging movement of said rocker arm in one direction.

ALTON SHUMAKE. 

